This invention is generally directed to photoconductive imaging members, and more specifically to imaging members with polyhydroxy ether resin binders. The present invention in one embodiment is directed to layered imaging members comprised of charge generating layers with charge photogenerating pigments dispersed in certain polyhydroxy ether resin binders. In a specific embodiment, the present invention relates to layered imaging members comprised of a photogenerating layer comprised of photogenerating pigments dispersed in a linear phenoxy resin binder and a charge, especially hole transport layer wherein the transport molecules thereof can be dispersed in a resinous binder. Further, in another embodiment of the present invention the imaging member is comprised of a supporting substrate, a photogenerating layer comprised of photogenerating pigments dispersed in a linear high molecular weight of from between about 50,000 to about 150,000 phenoxy resin binder, wherein the binder is present in an effective amount such as from between about 10 to about 60, and between about 15 to about 40 weight percent, and in contact therewith a charge, especially a hole transport layer comprised of hole transport molecules dispersed in a resinous binder. The charge transport layer can be located as the top layer of the imaging member or alternatively it may be situated between a supporting substrate and the photogenerating layer. Imaging members with the aforementioned poly(hydroxyether) binders can possess a number of advantages including, for example, excellent dispersion of the photogenerating pigment therein; achievement of uniform layers; excellent dispersion stability; acceptable coatability characteristics; higher loadings of photogenerating pigment because of the linear nature of the material selected; superior adhesion characteristics of the photogenerating layer to other layers; compatibility with charge transport molecules; superior solubility of the polymer; ease of dispersion formation; and the linear polymer is in many instances very pure.
The imaging members of the present invention can be selected for a number of known imaging, especially xerographic, and printing processes including electrophotographic imaging and printing processes.
The formation and development of electrostatic latent images on the imaging surfaces of photoconductive materials by electrostatic means is well known. Numerous different photoconductive members for use in xerography are known such as selenium, alloys of selenium, layered imaging members comprised of aryl amine charge transport layers, reference U.S. Pat. No. 4,265,990, and imaging members with charge transport layers comprised of polysilylenes, reference U.S. Pat. No. 4,618,551. The disclosures of the aforementioned patents are totally incorporated herein by reference. With the aforementioned imaging members, especially those of the '990 patent, there are selected aryl amine charge transport layers, which aryl amines are soluble in halogenated hydrocarbons such as methylene chloride. The resin binders of the present invention can also be selected as resinous binders for photogenerating layers of imaging members with electron transport layers, reference U.S. Pat. No. 4,474,865, the disclosure of which is totally incorporated herein by reference.
There is illustrated in U.S. Pat. No. 4,439,507, the disclosure of which is totally incorporated herein by reference, layered imaging members with photogenerating pigments dispersed in a poly(hydroxyether), reference for example the Abstract, the Figures, and columns 3 to 6. The layered imaging members of the present invention can be comprised of many of the same components of the aforementioned patent with the primary exception that there is selected as the resin binder for the members of the present invention linear, high molecular weight, poly(hydroxyethers) thereby enabling the advantages of the present invention, and more specifically superior dispersion of the photogenerating pigment as compared to the resin binders of the '507 patent.
In U.S. Pat. Nos. 4,869,988 and 4,946,754, the disclosures of which are totally incorporated herein by reference, there are described layered photoconductive imaging members with transport layers incorporating, for example, biaryl diarylamines, N,N-bis(biaryl)anilines, and tris(biarylyl)amines as charge transport compounds dispersed in a number of known resin binders. In the abovementioned patents, there are disclosed improved layered photoconductive imaging members comprised of a supporting substrate, a photogenerating layer optionally dispersed in an inactive resinous binder, and in contact therewith a charge transport layer comprised of the above-mentioned charge transport compounds, or mixtures thereof dispersed in resinous binders.
Examples of specific hole transporting components disclosed in U.S. Pat. No. 4,869,988 include N,N-bis(4-biphenylyl)-3,5-dimethoxyaniline (Ia); N,N-bis(4-biphenylyl)-3,5-dimethylaniline (Ib); N,N-bis(4-methyl-4'-biphenylyl)-3-methoxyaniline (Ic); N,N-bis(4-methyl-4'-biphenylyl)-3-chloroaniline (Id); N,N-bis(4-methyl-4'-biphenylyl)-4-ethylaniline (Ie); N,N-bis(4-chloro-4'-biphenylyl)-3-methylaniline (If); N,N-bis(4-bromo-4'-biphenylyl)-3,5-dimethoxy aniline (Ig); 4-biphenylyl bis(4-ethoxycarbonyl-4'-biphenylyl)amine (IIa); 4-biphenylyl bis(4-acetoxymethyl-4'-biphenylyl)amine (IIb); 3-biphenylyl bis(4-methyl-4'-biphenylyl)amine (IIc); 4-ethoxycarbonyl-4'-biphenylyl bis(4-methyl-4'-biphenylyl)amine (IId); and the like.
Examples of specific hole transporting compounds disclosed in U.S. Pat. No. 4,946,754 include bis(p-tolyl)-4-biphenylylamine (IIa); bis(p-chlorophenyl)-4-biphenylylamine (IIb); N-phenyl-N-(4-biphenylyl)-p-toluidine (IIc); N-(4-biphenylyl)-N-(p-chlorophenyl)-p-toluidine (IId); N-phenyl-N-(4-biphenylyl)-p-anisidine (IIe); bis(m-anisyl)-4-biphenylylamine (IIa); bis(m-tolyl)-4-biphenylylamine (IIIb); bis(m-chlorophenyl)-4-biphenylylamine (IIIc); N-phenyl-N-(4-biphenylyl)-m-toluidine (IIId); N-phenyl-N-(4-bromo-4'-biphenylyl)-m-toluidine (IVa); diphenyl-4-methyl-4'-biphenylylamine (IVb); N-phenyl-N-(4-ethoxycarbonyl-4'-biphenylyl)-m-toluidine (IVb); N-phenyl-N-(4-methoxy-4'-bipehnylyl)-m-toluidine (IVd); N-(m-anisyl)-N-(4-biphenylyl)p-toluidine (IVe); bis(m-anisyl)-3-biphenylylamine (Va); N-phenyl-N-(4-methyl-3'-biphenylyl)-p-toluidine (Vb); N-phenyl-N-(4-methyl-3'-biphenylyl)-m-anisidine (Vc); bis(m-anisyl)-3-biphenylylamin (Vd); bis(p-tolyl)-4methyl-3'-biphenylylamine (Ve); N-p-tolyl-N-(4methoxy-3'-biphenylyl)-m-chloroaniline (Vf), and the like. The aforementioned charge, especially hole transport components, can be selected for the imaging members of the present invention in embodiments thereof.
It is also indicated in the aforementioned patents that there may be selected as resin binders for the charge transport molecules those components as illustrated in U.S. Pat. No. 3,121,006 including polycarbonates, polyesters, epoxy resins, polyvinylcarbazole; and also wherein for the preparation of the charge transport layer with a polycarbonate there is selected methylene chloride as a solvent.
There is also mentioned as prior art U.S. Pat. No. 4,657,993, the disclosure of which is totally incorporated herein by reference, directed to polyphosphazene homopolymers and copolymers of the formula as recited, for example, in the Abstract of the Disclosure, which components may be selected as photoconductive materials and for other uses, see column 1, and continuing on to column 2; and as background interest directed to processes for the preparation of phosphonitrilic polymer mixtures, reference the Abstract of the Disclosure, U.S. Pat. No. 3,515,688 related to phosphonitrile elastomers, reference for example the Abstract of the Disclosure; U.S. Pat. No. 3,702,833 directed to curable fluorophosphazene polymers, see for example column 1; and U.S. Pat. No,. 3,858,712 directed to polyp polyphosphazene copolymers which are elastomers. The disclosures of each of the aforementioned patents are totally incorporated herein by reference.